JPH10180100A - Catalyst for hydrogen treatment of hydrocarbon oil and hydrogen treating method of gas oil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a catalyst for a hydrogen treatment of a hydrocarbon oil having a high hydrogenation activity to an arom. compd. together with a high resistance to sulfur and also having a high desulfurizing performance and to provide a production method of a gas oil blend base material having low sulfur content and low arom. compd. content by executing a contact reaction of the gas oil containing the arom. compd. by using the catalyst. SOLUTION: In the catalyst, 0.1-8mass% platinum group metal and 0.01-5mass% germanium based on the catalyst and expressed in terms of element are incorporated in a carrier consisting of alumina or an inorg. oxide consisting essentially of the alumina. The gas oil is subjected to the hydrogen treatment by executing the contact reaction of a gas oil fraction containing the arom. compd. at 3-8MPa hydrogen partial pressure, at 200-370 deg.C and at 0. 3-5hr<-1> liq. space velocity by using this catalyst.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a catalyst used in a hydrogenation reaction of a hydrocarbon oil to reduce the aromatic compound content and the sulfur content of the hydrocarbon oil, and to hydrogenate light oil using the catalyst. Regarding the treatment method, more specifically, a catalyst having high hydrogenation activity for aromatic compounds and high sulfur resistance, and also having high desulfurization performance, and using the catalyst, low sulfur content and The present invention relates to a method for producing a gas oil blend base material having a low aromatic compound content.

[0002]

BACKGROUND ART A diesel engine frequently used as an internal combustion engine is obtained by subjecting a straight gas oil fraction having a specific boiling point obtained by atmospheric distillation of crude oil or a hydrogen gas treatment to the straight gas oil fraction. The fuel is a gas oil fraction or a gas oil obtained by blending the gas oil fraction obtained from another source with the gas oil fraction as a main base material.

[0003] Gas oil straight cuts suitable for diesel engines contain only a limited amount of crude oil per unit amount of crude oil, and the available crude oil is becoming heavier every year. The content of the fraction tends to be further reduced. Therefore, in order to secure a necessary amount of the gas oil fraction, heavy oil is decomposed and converted into a gas oil base material.

[0004] On the other hand, demand for light oil is partly due to an increase in demand for light oil accompanying an increase in diesel engine vehicles.
It is expected to increase further, and it is expected that the supply of gas oil will be significantly short in the near future.

[0005] One method for dealing with the shortage of the gas oil fraction obtained as a straight cut from crude oil, in other words, for responding to an increase in demand for gas oil, is the production of a blend base material blended with the straight gas oil fraction. It is to increase.

[0006] Therefore, a light cracking gas oil (Light Cycle) having a specific boiling point range obtained from a catalytic cracking unit.
Oil (hereinafter abbreviated as LCO) has attracted attention as a feedstock oil for a new blend base material for light oil. This is because, contrary to the light oil fraction, LCO tends to be excessive due to the above-mentioned heavy crude oil, and it is desirable to divert the LCO to the blend base material in view of the supply and demand balance of the fraction.

[0007] However, since LCO contains a large amount of aromatic components, if LCO is blended as it is with a straight gas oil fraction, the content of aromatic compounds increases,
There is concern that the cetane number of the blended light oil will be reduced and the quality of the light oil will be reduced. In addition, since the content of the aromatic compound is high, there is a concern that when the blended light oil is used as a fuel for a diesel engine, the amount of generated particulates is significantly increased. Particulates are fine particulate air pollutants generated by incomplete combustion of some aromatic compounds, and the emission of large amounts of particulates into the atmosphere poses a serious environmental conservation problem. Will cause. In addition, LCO has a unique coloring, and if it is used as it is as a blend base material for light oil, the quality of the product light oil in terms of hue becomes a problem.

In order to solve such concerns and to use LCO as a good blend substrate, attempts have been made to subject LCO to catalytic hydrogenation to reduce the content of aromatic compounds in LCO. I have.

[0009] However, when the LCO is hydrogenated by the conventional method, the following problems occur. (1) Sulfur compounds contained in LCO in a relatively large amount and hydrogen sulfide generated by hydrotreating them inhibit the hydrogenation reaction of aromatic compounds and poison active sites on the catalyst. And cause deterioration of activity. (2) LCO has a high content of a high boiling point hardly desulfurizable sulfur compound (eg, 4,6-dimethyldibenzothiophene), although the total sulfur compound content is smaller than that of a straight-run gas oil fraction. Even if LCO is desulfurized, it requires deep desulfurization under severe conditions, which is not economically feasible. (3) Although the total sulfur content is lower than that of straight-run gas oil, LC
In O, the non-desulfurizable sulfur compound exists in a high composition ratio with respect to all the sulfur compounds. For this reason, depending on the properties of the feed oil and the standards required for the product oil, it is necessary to further reduce the sulfur content in the product oil to a predetermined level. There is a need for efficient and effective hydrogenation (desulfurization) performance that can be removed by hydrogenation.

[0010] Accordingly, there is a need for a hydrotreating catalyst for LCO, which is necessary for hydrotreating LCO to reduce aromatic compounds and for using LCO as a good blend base material for a gas oil fraction. The condition is to have both high hydrogenation activity for aromatic compounds and high sulfur resistance, and also to have high desulfurization performance capable of hydrogenating and removing hardly desulfurizable sulfur compounds.

Conventional catalysts which have been tried as LCO hydrotreating catalysts are roughly classified into two types, one of which is a hydrotreating catalyst mainly used for hydrotreating light oil. The other one is a group VIA metal-group VIII metal catalyst of the periodic table, for example, a desulfurization catalyst such as a CoMo or NiW catalyst using an alumina carrier.

However, the above hydrotreating catalyst contains a metal species having poor sulfur resistance, such as nickel, palladium, and platinum, as an active component of the catalyst. It works effectively only in a low sulfur atmosphere of less than ppm. For this reason, it is technically difficult to use the above hydrotreating catalyst for hydrotreating LCO having a higher sulfur compound content.

The above desulfurization catalyst is a typical hydrodesulfurization catalyst used in a petroleum refining process, and is originally a catalyst intended for hydrodesulfurization. However, the hydrogenation performance of aromatic compounds is not sufficient. For this reason, the above desulfurization catalyst is
To use as a catalyst for CO hydrotreating and hydrogenate aromatic compounds to convert them into naphthenes, under a high hydrogen partial pressure of about 10 MPa, depending on other conditions such as the properties of the feedstock and the reaction temperature, it may be higher. It is necessary to carry out the hydrogenation treatment under a high hydrogen partial pressure, which increases equipment costs and operating costs. Instead of increasing the hydrogen partial pressure, the reaction rate can be increased by increasing the reaction temperature to promote the conversion of the aromatic compound.However, increasing the reaction temperature is not suitable for the exothermic hydrogenation reaction. Not only is it disadvantageous in terms of reaction equilibrium, but also side reactions such as a decomposition reaction and a polycondensation reaction remarkably proceed, so that the yield of a hydrogenated product is reduced, which is not economical. In addition, since the reaction is a high temperature reaction, the problem of the hue of the produced oil is not improved, and further, there is a problem that the equipment cost and the operating cost of the device are increased.

As described above, conventional catalysts have both high hydrogenation activity for aromatic compounds and high sulfur resistance, and have excellent desulfurization performance even for hardly desulfurizable sulfur compounds. Therefore, it was not suitable for the treatment used in the hydrogenation reaction of LCO to reduce the aromatic compound content of LCO.

[0015]

Accordingly, an object of the present invention is, firstly, to provide a catalyst suitable for reducing the aromatic compound content by hydrotreating a hydrocarbon oil, particularly a gas oil fraction. The second is to provide a method for hydrotreating a gas oil fraction using the catalyst.

[0016]

SUMMARY OF THE INVENTION The present inventors have conducted various studies to solve the above-mentioned problems. As a result, first, (a) in order to reduce aromatic compounds by nuclear hydrogenation, a platinum group metal-based catalyst was used. Is promising. However, as mentioned above,
Since the platinum group metal-based catalyst has low sulfur resistance, studies for increasing the sulfur group were repeated. As a result, (b) surprisingly, if germanium is supported together with the platinum group metal, the platinum group metal has a high dispersion. As described in (e) below, not only the sulfur resistance is remarkably improved, but also the nuclear hydrogenation action of the aromatic compound is suppressed. (C) significantly improved.
If the acid property of the catalyst has a predetermined value, the sulfur resistance and the nuclear hydrogenation of the aromatic compound are remarkably improved. (D) The carrier is composed of alumina or alumina as a main component. The acid properties of a catalyst which is an inorganic oxide whose active metal is a platinum group metal and which contains a specific amount of germanium can be easily adjusted. (E) According to this catalyst, it can be carried out at a relatively low cost. Under the conditions of a high hydrogen / oil ratio and a hydrogen partial pressure and a reaction temperature substantially similar to those of the conventional hydrogenation, the deterioration of the activity due to sulfur compounds and the like is suppressed. It has been found that the catalyst exhibits higher hydrogenation activity for aromatic compounds than a desulfurization catalyst and a platinum-based hydrogenation catalyst.

The present invention is based on the above findings. [1] A carrier made of alumina or an inorganic oxide containing alumina as a main component is coated on a catalyst basis in an amount of 0.1% in terms of metal.
A catalyst for hydrotreating hydrocarbon oils, characterized in that the catalyst contains a platinum group metal of from 8 to 8 mass% and germanium of from 0.01 to 5 mass%, and [2] in the presence of the above-mentioned catalyst. Carrying out a catalytic reaction of a gas oil fraction containing an aromatic compound at a hydrogen partial pressure of 3 to 8 MPa, a temperature of 200 to 370 ° C., and a liquid hourly space velocity of 0.3 to 5 hr ⁻¹ . The gist of the hydrotreating method is as follows.

The catalyst of the present invention is suitable for hydrotreating hydrocarbon oils, especially gas oil fractions, for example, catalytic cracking gas oil, straight run gas oil, pyrolysis gas oil, hydrotreated gas oil, desulfurized gas oil, etc. ing. As typical properties of these feedstocks,
Boiling range: 150 to 450 ° C, sulfur content: 2000 mass p
pm or less, preferably 500 ppm by mass or less, and aromatic compounds: in the range of 5 to 90% by volume.

The carrier of the catalyst of the present invention is alumina or a mixture of alumina as a main component and an inorganic oxide other than alumina. As this alumina, various aluminas such as α-alumina, β-alumina, γ-alumina and δ-alumina can be used, but porous alumina having a high specific surface area is preferable, and γ-alumina is particularly suitable. ing. Alumina contains unavoidable impurities, and these unavoidable impurities are distinguished from the above-mentioned inorganic oxides.

Inorganic oxides other than alumina (hereinafter referred to as carrier subcomponents) include, as a first group, silica, boria, titania, zirconia, magnesia, hafnia,
Ceria, yttria, niobia, chromia, thoria and the like can be mentioned, and these are used alone or in combination of two or more.

The group of the second carrier subcomponents is a crystalline inorganic oxide such as zeolite and molecular sieve, or a clay mineral such as montmorillonite, kaolin, bentonite, saponite and the like. These may be used alone or in combination of two or more. To use.

The third group of carrier subcomponents includes inorganic oxides obtained by activating specific metal oxides such as zirconia and titania with sulfate ions, for example, SO ₄ / ZrO ₂ , SO ₄ / TiO _2
And these are used alone or in combination of two or more.

In addition, two or more of the first to third carrier subcomponents are arbitrarily selected and used (for example, the first to third carrier subcomponents).
And the third group of SO ₄ / ZrO ₂ may be used in combination.

The content of the carrier subcomponent in the carrier is 5 to 50% by mass, preferably 10 to 10% by mass, based on the carrier, in terms of oxide.
40% by mass.

The specific surface area, pore volume, and average pore diameter of the carrier composed of the above alumina and the carrier auxiliary component are not particularly limited, but they are excellent in sulfur resistance and are suitable for hydrogenation of hydrocarbon oils. In order to obtain a catalyst having a high activity and desulfurization activity, the specific surface area is in the range of 100 to 600 m ² / g, preferably 200 to 400 m ² / g, and the pore volume is in the range of 0.
It is in the range of 4 to 1.2 ml / g, and the average pore size is 50 to
Those in the range of 200 °, preferably 50-150 °, are suitable. The carrier is D ammonia-TPD
It is preferable that the acid amount measured by the method is 0.6 to 3.5 mmol / g.

The platinum group metal of the active ingredient to be supported on the carrier can be platinum, palladium, rhodium, ruthenium, osmium, or iridium, either alone or in combination of two or more, preferably platinum. The platinum group metal is supported in the form of a compound, and specific examples of the compound include metal chlorides, chlorides, nitrates, sulfates, acetates, phosphates, and organic acid salts. Acid salts, chlorides and nitrates. These platinum group metals or these compounds may be supported alone,
Two or more types can be supported in combination.

The content of the platinum group metal is 0.1 to 8% by mass, preferably 0.2 to 2% by mass in terms of metal on a catalyst basis. If the platinum group metal is less than 0.1% by mass, the active sites attributed to the platinum group metal cannot be sufficiently obtained, and if it exceeds 8% by mass, the dispersibility of the active metal is poor due to aggregation of the platinum group metal compound and the like. Not only does this increase the content of the active metal but also increases the cost because it exceeds the limit of the content of the active metal to be dispersed efficiently.

Specific examples of the germanium compound supported together with the platinum group metal compound include germanium tetrachloride, germanium difluoride, germanium tetrafluoride, germanium diiodide, germanium monosulfide, and similar compounds thereof. These may be supported alone or in combination of two or more.

The germanium content is 0.01 to 5% by mass, preferably 0.1 to 5% by mass in terms of oxide on a catalyst basis.
It is 2% by mass, more preferably 0.1 to 1% by mass. Germanium improves the dispersibility of the platinum group metal, suppresses sintering of the platinum group metal, and suppresses coke deposition and sulfur deposition on the platinum group metal. If the content of germanium is less than 0.01% by mass, it is insufficient to exert these effects. If the content exceeds 5% by mass, not only the platinum group metal but also the reactive active sites present on the carrier are covered. As a result, no improvement in catalytic activity is observed.

In the present invention, a halogen may be contained together with the platinum group metal and germanium in order to make the acidity of the catalyst more suitable. As the halogen, when a halide such as a metal chloride or chloride is used as the compound of the platinum group metal and germanium, or a halide such as hydrochloric acid is used as a solvent component or the like in preparing a catalyst described later. In this case, the compound may be derived from these compounds, or when a compound other than a halide is used, or when only a halogen derived from a halide is insufficient, another halogen may be added together with this compound. Sources, for example, chlorine, hydrochloric acid, perchloric acid, hydrofluoric acid, chlorine dioxide, stabilized chlorine dioxide solution, fluorine, hydrofluoric acid, ammonium acid fluoride, bromine, ammonium bromide, iodine, hydroiodic acid, etc. Just use it.

Halogen acts to further improve the acidity of the catalyst. When the catalyst exhibits a suitable acidity, the dispersibility of the active ingredient is improved and the acid point on the carrier is improved. Shows an optimum value to promote the adsorption of the aromatic compound and improve the hydrogenation activity of the aromatic compound. If the acidity of the catalyst is too high due to too much halogen, undesired side reactions such as over-decomposition of aromatic compounds are caused. As described above, when halogen is contained, the content thereof is 0.05 to 3% by mass, preferably 0.1 to 3% by mass, in terms of element, based on the catalyst in order to make the acidity of the catalyst a suitable value. 1% by mass.

The catalyst of the present invention comprising the above components has an acid content of 0.4 to 3 mm as measured by the ammonia-TPD method.
ol / g is preferred. Where ammonia-
TPD (Temperature Program)
The d Desorption method refers to the sample (ie,
A predetermined amount of a carrier or a catalyst is filled in an adsorption tube, and as a pretreatment, the temperature is raised to a predetermined temperature in an inert gas flow for a predetermined time, kept at the same temperature in the same gas flow for a predetermined time, and cooled to room temperature for a predetermined time. After lowering the temperature and performing ammonia adsorption for a predetermined time at room temperature and normal pressure, in a state where the above inert gas is flown, perform deaeration for a predetermined time at a predetermined temperature under a predetermined reduced pressure. A method in which an ammonia desorption spectrum is observed in the above-mentioned inert gas stream at a predetermined heating rate, and the amount of acid is specified by the amount of ammonia obtained from this spectrum.

When the acid amount is less than 0.4 mmol / g, high dispersibility of the platinum group metal cannot be secured, and it becomes difficult to reduce the electron density of the platinum group metal. The effect of improving nuclear hydrogenation and the effect of improving sulfur resistance cannot be sufficiently obtained. When the amount is more than 3 mmol / g, undesired side reactions such as overcracking of a feed oil fraction are caused. Incidentally, in the catalyst of the present invention, the acid amount is 0.4
When the content of each component is within the above-mentioned predetermined range of the present invention, the object of the present invention (nuclear hydrogenation of an aromatic compound or sulfur-desulfurizing sulfur compound) Reduction, etc.) can be achieved more effectively.

The catalyst of the present invention can be prepared by a known method. For example, a solution prepared by dissolving a compound of the active ingredient and, in some cases, a halogen source in a solvent such as an acid, water, or an alcohol is subjected to one or more impregnation treatments of impregnating the carrier with the active ingredient and a halogen. Is carried out. As a solvent at this time,
For example, an acidic solvent such as hydrochloric acid, nitric acid, and sulfuric acid can be used. After the impregnation, drying and baking are performed. If the number of times of the impregnation is plural, drying and baking may be performed for each impregnation.

The order in which the platinum group metal compound and the germanium compound or the halogen source is impregnated is not particularly limited, and the order of the platinum group metal compound, the germanium compound and the halogen source is not limited even when the halogen is contained. May be impregnated sequentially or simultaneously. It is preferable to impregnate simultaneously from the viewpoint of the properties of the product catalyst such as acidity and pore properties, or the operability.

As another method, a kneading method in which a part or all of an active ingredient and, in some cases, a part or all of a halogen source are mixed with a carrier material before molding as a carrier and integrally molded, A precipitation method is exemplified.

The specific surface area, pore volume and average pore diameter of the catalyst of the present invention prepared by the above-mentioned catalyst preparation method are not limited as long as the function as a catalyst is exhibited. In order to increase the hydrogenation activity and desulfurization activity for hydrocarbon oils as in the case of the above-mentioned carriers, those having the following values are suitable.

[0038] The specific surface area is preferably ^{100~600m 2 / g, 200~400m 2 /} g is more preferable. The pore volume is preferably 0.4 to 1.2 ml / g,
0.9 ml / g is more preferred. Average pore size is 50 ~
200 ° is preferable, and 50 to 150 ° is more preferable.
If the average pore diameter is less than 50 °, the reactants are difficult to diffuse into the pores, and the hydrogenation reaction of the aromatic compound and the hardly desulfurizable sulfur compound does not proceed efficiently. 200Å
If it is larger, the diffusivity in the pores is good, but the surface area in the pores decreases, so that the effective specific surface area of the catalyst decreases and the activity decreases.

In order to increase the effective number of pores satisfying the above pore conditions, the pore size distribution of the catalyst (that is, the ratio of the pores having a mean pore diameter of ± 15 °) is 70%.
Or more, more preferably 80% or more.

The method for hydrotreating light oil of the present invention using the above-mentioned catalyst can be carried out under a hydrogen partial pressure of 3 to 8 MPa, 200 to 37 MPa.
At a temperature of 0 ° C. and a liquid hourly space velocity of 0.3 to 5 hr ⁻¹ , the catalyst is brought into contact with a light oil fraction containing an aromatic compound, and the aromatic compound is subjected to nuclear hydrogenation to produce an aromatic compound. This is a method for reducing the content of sulfur and the content of sulfur compounds such as non-desulfurization. The typical properties of the gas oil fraction containing the aromatic compound are the same as those described above as examples of the properties of the feedstock oil to which the catalyst of the present invention can be applied.

In order to carry out the hydrotreating method of the present invention on a commercial scale, a fixed bed, a moving bed or a fluidized bed type catalyst layer of the catalyst of the present invention is formed in a reactor, and the catalyst is formed in the reactor. The feedstock may be introduced and the hydrogenation reaction may be performed under the above conditions.
Most commonly, a fixed bed catalyst bed is formed in a reactor,
Feeding the feedstock to the top of the reactor, passing it through the fixed bed from top to bottom, and allowing the product to flow out of the bottom of the reactor,
Conversely, feedstock is introduced into the lower part of the reactor, passes through the fixed bed from bottom to top, and the product flows out from the upper part of the reactor.

The catalyst of the present invention can be used in the case where a single reactor is charged to perform a single-stage hydrotreating, or the catalyst of the present invention is charged in several reactors and a multi-stage continuous hydrotreating is performed. It can also be used when performing In particular, when the feedstock is relatively heavy, it is preferable to perform multi-stage hydrotreating.

[0043]

【Example】

[Preparation of Catalyst] The measurement procedure of the catalyst prepared in the following Examples and Comparative Examples and the carrier before preparation by the ammonia-TPD method was as follows. Sample (carrier and catalyst) using ammonia-TPD device manufactured by Bell Japan
0.1 g was charged into an adsorption tube, and the temperature was raised to 500 ° C. in a He gas stream over 50 minutes as a pretreatment, and 500
C. for 1 hour, and cooled to room temperature in 11 minutes and 30 seconds.
After adsorbing ammonia for 15 minutes at room temperature and normal pressure,
e at 100 ° C. under reduced pressure of 150 Torr
For 12 minutes and 30 seconds. With respect to the degassed sample, an ammonia desorption spectrum was observed in a He gas flow at a temperature rising rate of 10 ° C./min, and the total ammonia desorption amount was obtained and defined as an acid amount.

EXAMPLE 1 A silica-alumina having a pore volume of 0.71 ml / g and a surface area of 363 m ² / g (a silica / alumina weight ratio = 20/80, a columnar molded product having a diameter of 1/16 inch) was placed in an eggplant-shaped flask. , Acid amount 0.66 mmol / g), into which 39.02 g was added. To the solution were added 32.38 g of a 0.1 N aqueous hydrochloric acid solution, 0.5219 g of chloroplatinic acid hexahydrate, and germanium tetrachloride 0.1%.
A solution in which 2380 g was dissolved was added using a pipette. After immersion at about 25 ° C. for 2 hours, it was air-dried, and the temperature of the immersion mixture was raised to 120 ° C. in a muffle furnace and dried for about 1 hour. Next, the mixture was calcined at 500 ° C. for 4 hours to obtain a catalyst A.

The composition of the catalyst A was Pt (0.56% by mass).
-Ge (0.28% by mass) -Cl (0.16% by mass) /
It was SiO ₂ —Al ₂ O ₃ (99.0% by mass). The physical properties of the catalyst A were a surface area of 311 m ² / g, a pore volume of 0.71 ml / g, and an average pore diameter of 66 °. Catalyst A
Was 0.60 mmol / g.

Example 2 39.2 g of the same silica-alumina as used in Example 1 was charged into an eggplant-shaped flask, and 0.5000 g of chloroplatinic acid hexahydrate was added to 32.38 g of ion-exchanged water. And a solution in which 0.1161 g of water-soluble germanium dioxide was dissolved was added using a pipette, and impregnation, drying, and calcining were performed under the same conditions as in Example 1 to obtain Catalyst B.

The composition of the catalyst B was Pt (0.51% by mass).
-Ge (0.27% by mass) / SiO ₂ -Al ₂ O ₃ (9
9.22% by mass). The physical properties of the catalyst B were a surface area of 309 m ² / g, a pore volume of 0.72 ml / g, and an average pore diameter of 66 °. The acid amount of the catalyst B is 0.51 mmol
1 / g.

Comparative Example 1 47.67 g of alumina having a pore volume of 0.73 ml / g and a surface area of 380 m ² / g (a columnar molded product having a diameter of 1/16 inch, an acid amount of 0.56 mmol / g) was placed in an eggplant-shaped flask. Was added thereto, and an aqueous solution obtained by dissolving 0.6360 g of chloroplatinic acid hexahydrate in 39.57 g of ion-exchanged water was added using a pipette, and impregnated under the same conditions as in Example 1, dried, and dried.
Calcination was performed to obtain Catalyst C.

The composition of the catalyst C was Pt (0.53% by mass).
—Cl (0.46% by mass) / Al ₂ O ₃ (99.01% by mass). The physical property of the catalyst C was 315 m in surface area.
² / g, pore volume 0.68 ml / g, average pore diameter 66 °
Met. The acid amount of the catalyst C was 0.44 mmol.

Comparative Example 2 Into an eggplant-shaped flask, 48.25 g of the same silica-alumina as used in Example 1 was charged, and 34.2 g of the same were added thereto.
0.6437 chloroplatinic acid hexahydrate in 5 g of ion-exchanged water
The aqueous solution in which g was dissolved was added using a pipette, and impregnation, drying, and calcination were performed under the same conditions as in Example 1 to obtain Catalyst D.

The composition of the catalyst D was Pt (0.50% by mass).
—Cl (0.17% by mass) / SiO ₂ —Al ₂ O ₃ (9
9.33% by mass). The physical properties of the catalyst D were a surface area of 306 m ² / g, a pore volume of 0.72 ml / g, and an average pore diameter of 65 °. The acid amount of the catalyst D is 0.53
mmol.

[Hydrogenation Reaction of Desulfurization Decomposition Gas Oil] Examples 3 to 6, Comparative Examples 3 to 6 Using the catalysts A to D prepared in the above Examples and Comparative Examples,
In the following manner, the hydrotreating of the desulfurized cracked gas oil having the following properties was performed. That is, first, the catalyst was charged into a reactor of a high-pressure flow reactor to form a fixed-bed catalyst layer, which was pretreated under the following pretreatment conditions. Next, a mixed fluid of the feedstock oil and the hydrogen-containing gas heated to the reaction temperature is introduced from the upper part of the reactor, and the hydrogenation reaction proceeds under the following conditions. The oil was discharged from the lower part of the reactor, and the produced oil was separated by a gas-liquid separator.

Catalyst pretreatment conditions Pressure (hydrogen partial pressure); 4.9 MPa atmosphere; hydrogen gas flow temperature; 150 ° C. for 1.5 hr, then 300 ° C. for 2 hr. Reaction temperature: 300 or 350 ° C. Pressure (hydrogen partial pressure): 4.9 MPa Liquid space velocity: 1.5 hr ⁻¹ hydrogen / oil ratio: 560 m ³ / m ³ Properties of feed oil Oil type: Desulfurization cracked gas oil Specific gravity ( 0.9078 distillation property; initial boiling point: 177.0 ° C, 50% point: 276.0 ° C, 90% point: 341.1 ° C, end point: 35
5.5 ° C. Sulfur content; 180 mass ppm Saturated hydrocarbon component; 30.9% by volume Olefin component: 0.0% by volume Single aromatic component: 45.3% by volume Bicyclic aromatic component: 19.8% by volume Ring aromatic component: 4.0% by volume Total aromatic component: 69.1% by volume Saybolt color: -16 or less

The reaction results were analyzed by the following method. The reactor was operated at a reaction temperature of 300 ° C. or 350 ° C., respectively, and after 6 days, each produced oil sample was collected and analyzed for its properties. The dearomatization rate was defined as the rate at which the aromatic component in the feed oil was reduced by the hydrogenation reaction, and was calculated from the analysis value of the aromatic component in the feed oil and product oil by the formula shown in Equation 1. . Further, based on the analysis value of the aromatic content in the feed oil and the produced oil and the liquid hourly space velocity,
The reaction rate constant was calculated by the formula shown in (1) to evaluate the easiness of the progress of the hydrogenation reaction. In addition, the higher the reaction rate constant,
It shows that the catalyst activity is excellent. These results were as shown in Table 1.

[0055]

## EQU1 ## Dearomatization rate (%) = [(A _F -A _P ) /
A _F] × 100 _{A F:} feedstock aromatic content of (volume%) _{A P:} aromatics in the reaction product oil (% by volume) dearomatization rate constant _{= ln (A F / A P} ) × LHS
VLHSV: liquid hourly space velocity (hr ^-1 )

[0056]

[Table 1-1]

[0057]

[Table 1-2]

As can be seen from Table 1, the catalysts A and B of the present invention
Has a lower content of aromatic compounds in the product oil than the comparative catalysts C and D under the same reaction conditions. This is because the catalyst of the present invention has a high hydrogen / oil ratio of 560 m ³ / m ³ and a hydrogen partial pressure and a reaction temperature which are almost the same as those of the conventional hydrotreating. It shows that it is effective for the chemical reaction.

[0059]

As described in detail above, according to the present invention,
The following effects can be obtained. (1) The aromatic compound has high nuclear hydrogenation activity and also has high sulfur resistance, so that the content of the aromatic compound in the hydrocarbon oil can be significantly reduced. (2) Under the same conditions as conventional hydrotreating conditions, the hydrotreating of an aromatic compound in a feedstock having a sulfur content of several hundred ppm by mass can be efficiently performed. (3) Even hydrocarbon oils such as LCO containing a large amount of aromatic compounds can efficiently reduce aromatic compounds and sulfur compounds by hydrogenation. (4) A light oil base material capable of suppressing the generation of particulates in exhaust gas and having a low sulfur content can be supplied at low cost. (5) Since the reaction conditions can be made substantially the same as the reaction conditions in the conventional hydrotreating, the conventional apparatus can be diverted without significant modification.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Takashi Fujikawa, Inventor 4-20-2-402, Hanaguri, Soka City, Saitama Prefecture (72) Inventor, Yukio Shibata 4-20-4-403, Hanaguri, Soka City, Saitama Prefecture

Claims (2)

[Claims] 1. A carrier comprising alumina or an inorganic oxide containing alumina as a main component, on a catalyst basis, in terms of elements,
A catalyst for hydrotreating hydrocarbon oils, comprising 0.1 to 8% by mass of a platinum group metal and 0.01 to 5% by mass of germanium. 2. In the presence of the catalyst according to claim 1, 3 to 8
Hydrogen partial pressure of MPa, temperature of 200-370 ° C, and 0.
A method for hydrotreating gas oil, comprising conducting a contact reaction of a gas oil fraction containing an aromatic compound under the conditions of a liquid hourly space velocity of 3 to 5 hr ^-1 .